title: Emerging roles for diverse intramembrane proteases in plant biology.
abstract: Progress in the field of regulated intramembrane proteolysis (RIP) in recent years has made its impact on plant biology as well. Although this field within plant research is still in its infancy, some interesting observations have started to emerge. Gene encoding orthologs of rhomboid proteases, site-2 proteases (S2P), presenilin/γ-secretases, and signal peptide peptidases are found in plant genomes and some of these gene products were identified in different plant cell membranes. The lack of chloroplast-located rhomboid proteases was associated with reduced fertility and aberrations in flower morphology. Mutations in homologues of S2P resulted in chlorophyll deficiency and impaired chloroplast development. An S2P was also implicated in the response to ER stress through cleavage of ER-membrane bZIP transcription factors, allowing their migration to the nucleus and activation of the transcription of BiP chaperones. Other membrane-bound transcription factors of the NAC and PHD families were also demonstrated to undergo RIP and relocalization to the nucleus. These and other new data are expected to shed more light on the roles of intramembrane proteases in plant biology in the future. This article is part of a Special Issue entitled: Intramembrane Proteases.
authors.affiliation: The Robert H. Smith Institute of Plant Sciences and Genetics in Agriculture, The Hebrew University of Jerusalem, Rehovot 76100, Israel. Electronic address: zach.adam@mail.huji.ac.il.
authors.forename: Zach
authors.initials: Z
authors.lastname: Adam
mesh_terms: D017360:Arabidopsis / Q000201:enzymology* / Q000235:genetics; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D050976:Basic-Leucine Zipper Transcription Factors / Q000235:genetics / Q000378:metabolism; D002462:Cell Membrane / Q000201:enzymology* / Q000235:genetics; D002467:Cell Nucleus / Q000235:genetics / Q000378:metabolism; D002736:Chloroplasts / Q000201:enzymology* / Q000235:genetics; D010450:Endopeptidases / Q000235:genetics / Q000378:metabolism*; D059865:Endoplasmic Reticulum Stress; D018832:Molecular Chaperones / Q000235:genetics / Q000378:metabolism; D009154:Mutation; D021381:Protein Transport; D015398:Signal Transduction
chemical_list: D029681:Arabidopsis Proteins; D050976:Basic-Leucine Zipper Transcription Factors; D018832:Molecular Chaperones; D010450:Endopeptidases
keywords: Arabidopsis thaliana; Chloroplast; ER stress; Plant; Protease